Exhibit 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statement on Form S‑8 (No. 333-177517) of United Technologies Corporation of our report dated June 26, 2013 relating to the financial statements of the United Technologies Corporation Represented Employee Savings Plan, which appears in this Form 11-K.

/s/ PricewaterhouseCoopers LLP

Hartford, Connecticut

June 26, 2013

23